+1 @dekay I am with you on your responses.
Also @sudnh is right on money:
Sounds more to me like you put together a poor sounding main audio system like many people do and you are now in lament.
If anything I have found that the better your system is able to bring out the "liveliness" or make your music "more alive", the more you enjoy your music and start exploring genres that I found boring before. If the OP put together a system that probably sounds analytical or "not interesting enough", then let's they probably learned a valuable lesson to not spend money just because they have them. I have to guess that the second system costs close to $4k (used?). and 25X of that....strange!
But also one more point I note is the "open floor". Music often "blooms" in such space and it is beautiful. Not sure about OP's down stair room. So if the OP would have hauled his "primary system" into the "open space" and then decided before selling, then that would have made sense. Hope they did that. But like @dekay , I am not sold on this post.